如何在Perl中将块(键和值)从散列中移位？

# 创建一个散列
my %hash = (
    'key1' => 'value1',
    'key2' => 'value2',
    'key3' => 'value3'
);

# 打印原始散列
print "Original hash: ", join(', ', %hash), "\n";

# 移除键为'key2'的项
delete $hash{'key2'};

# 打印更新后的散列
print "Updated hash: ", join(', ', %hash), "\n";

Original hash: key1 => value1, key2 => value2, key3 => value3
Updated hash: key1 => value1, key3 => value3

# 移除散列中的所有项
%hash = ();

# 移除散列中的所有项
undef %hash;

if (exists $hash{'key2'}) {
    delete $hash{'key2'};
} else {
    print "Key 'key2' does not exist in the hash.\n";
}